Modulators for various wireless communication systems are known in the art. Specifically, different modulators exist for modulating wireless communication signals sent under different communication schemes. For example, data or voice communications must be modulated into a signal that a mobile station, such as a cell phone or other mobile communication device, can send or receive. Many wireless communication schemes are known in the art such as Global System for Mobile communications (“GSM”), General Packet Radio Service (“GPRS”), EDGE (Enhanced Data rates for Global Evolution), and so forth. Each of these communication schemes has a unique modulation method for transmitting data such as Gaussian Minimum Shift Keyed (“GMSK”), 8 Phase Shift Keyed (“8PSK”), and so forth.
Given the number of wireless communication schemes, there is a need for mobile stations and base stations that can receive and transmit information in more than one wireless communication scheme or modulation method. To transmit and receive data in multiple schemes or modulations, however, a base/mobile station typically needs a different modulator for each transmission method, and including multiple modulators increases the amount of circuitry and logic resources used within a base/mobile station and the amount of battery drain on the mobile station. Alternatively, a base/mobile station may use a single modulator that is adapted to modulate data in more than one communication scheme—known modulators with such a capacity typically need increased logic and memory resources to perform the necessary calculations and conversions to modulate a signal in more than one wireless communication scheme. Moreover, known modulators do not effectively incorporporate predistortion of the modulated signal to correct for certain errors in the signal introduced by, for example, a power amplifier that amplifies the modulator's output.
Also, the various communication schemes are regulated by various standards which must be met. As such, a further problem is ensuring that the wireless communication signals created by these modulators meet the various standards for the communication schemes.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention. It will further be appreciated that certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the arts will understand that such specificity with respect to sequence is not actually required. It will also be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study except where specific meanings have otherwise been set forth herein.